@ englad:
You can say what you want. Ich bin hier nicht die Polizei. lol. Hardcore bashing of someone's culture, religion, etc. is never going to sit well with anyone. You can expect a lot of backlash unless the person you're insulting is somehow not bothered by it (person hates his own country/culture, etc). If it is less serious bashing, then it won't be perceived as negatively - it may even be taken humorously. My only advice is, is that you only call out certain groups of a certain country (as you've already said); this way, you don't sound as if you're painting the whole culture/society with the same brush. But, again, you can do what you want. The consequences thereof are your responsibility.
There is a strong level of arrogance and pride evoked when feeling that your entire culture and country have been attacked. It is only natural for many. People are by nature very tribal. It's written in our DNA. Ist das ein gute Ding? Aber nein, ganz und gar nicht!
We lack common decency in our interactions with other people. That is another story, however.
Again, no culture is perfect. Japanese society has its share of problems for sure. You can be, nonetheless, too direct and frank. I prefer societies that are much less so. But it's best, I suppose, to find a happy medium, which is not easy, considering that people are attracted to polar extremes.
Japan has super low crime and social harmony because it's best on buddhist concepts; for example, the individual is not as important as the greater good of society. It's all a trade-off.
Disagreeing with someone
in some contexts is just plain rude. It is a major turn-off. Again, it comes down to personality as much as culture. Some people naturally tolerate cultural disrespect and directness better than others. That said, there are people in every society who enjoy disagreeing for the sake of disagreeing (
l'esprit de contradiction).
We all need to try to get along better and to stop being so tribal and impolite. I know these are empty words.
Peace.
